Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Capitalization, Equity [Line Items]
Preferred Stock, shares authorized	20,000,000
Par value of preferred stock (per share)	$ 0.1
Common stock, shares authorized	100,000,000	100,000,000
Par value of common stock (per share)	$ 0.1	$ 0.1
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, shares outstanding	51,270,940	51,326,751
Stock Repurchased and retired during period, Shares	(100,000)	(1,200,000)	(3,200,000)
Repurchases of common stock	$ (3.8)	$ (43.5)	$ (115.5)
Company Action Level RBC, as Percentage of Authorized Control Level RBC	200.00%
Dividends paid	$ 49.2	49.7	51.8
Amount available for dividend payment	269.0
Kemper's Insurance Subsidiaries [Member]
Schedule of Capitalization, Equity [Line Items]
Cash dividends paid by Kemper's Insurance Subsidiaries to Kemper	104.5
Amount available for dividend payments	133.0
Amount of restricted net assets for consolidated and unconsolidated subsidiaries	2,400.0
Life and Health [Member]
Schedule of Capitalization, Equity [Line Items]
Statutory capital and surplus for the Company’s life and health insurance subsidiaries	403.7	394.6
Statutory net income for the Company’s life and health insurance subsidiaries	29.7	62.8	100.7
Statutory capital and surplus required	121.4
Property and Casualty Insurance [Member]
Schedule of Capitalization, Equity [Line Items]
Statutory capital and surplus for the Company’s life and health insurance subsidiaries	928.9	957.7
Statutory net income for the Company’s life and health insurance subsidiaries	1.4	$ 58.9	$ 85.7
Statutory capital and surplus required	$ 334.1
Restricted Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Common stock, shares outstanding	16,000	80,848